Preservation of fresh fruit



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May 18 1926.,

E. M. BROGDEN PRESERVATIION OFFRESH FRUIT Filed MaIGh 8, 1922 2 Sheets-Sheet 1 @19055 M rogdew,

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May 18 i926..

E. M. BROGDEN PRESERVATION OF FRESH FRUIT Filed MaICh 8 1922 2 Sheets-Sheet 2 ,Patented 4May 18,1926.

UNITED s'mxrl-:s

PATENT OFFICE.

ERNEST M. BROGDEN, F WINTER HAVEN, FLORIDA, ASSIGNOR, BY HESNE ASSIGN- MENTS, TO BROGDEX COMPANY, OF WINTER HAVEN, FLORIDA, AYCORPORATION 0F FLORIDA..

PRESERVATION 0F FRESH FRUIT.

Application illed 'March .8, 1922. SerialNo. 542,141.

This invention relates to preservation of fresh fruit; and in particular to the treatment of grapefruit, oranges, lemons, apples, etc., with a coating composition comprising a waxy material and a liquid vehicle consisting principally or wholly of kerosene, so

. compounded as to be spreadable over` the surface Iof the fruit to produce a lm-hke waxy .coating that effectively prevents evaporation of the fruit juices and infection of the fruit by mold or rot organisms, and maintains the fruit in its original firm, plump, and fresh condition for relatively long periods of time. lin prior copending applications I have l5 disclosed and claimed compositions and methods for preserving' fresh. cltrus and other fruits, characterized in generalb the employment of a waxy material suo as paraiiin, intimately commixed with a solvent vehicle, such as asoline, of a falrly7 high de ee of volati ity. I have found that, un er roper conditions, it is 1possible and frequent y advantageous to emp oyaless volatile vehicle, specifically kerosene, to take the place of the gasoline either wholly or in art. The term kerosene is herein used to include any of the mineral oil distlllates falling within the cut or fraction to whlch the name is commonl given. It is to be under.-

3 stood also that t e term, fruit as employed herein com rehends also other vegetable,

roducts suc as cucumbers, tomatoes, cantaoupe, or the like, which can advantageously be treated for preservation in accordance with the presentinvention. v

For the sake of a concrete illustrativev example from which' the principles of the invention can be fully understood, reference will be made hereinafter more particularly to the preservative treatment of citrus fruits, but it 1s not to be inferred that the invention is `limited thereto. v

In applying the principles of the invention to treatlng citrus fruit, the best procedure now known to me is first to spread athin. -coatin of the paraiin-kerosene mixture all over t e surface of the fruit, then to remove a substantial portion of the kerosene by passing .the fruit through suitable evaporating or dryin apparatus andiimally to give the fruit a t orough ru bing by means ot apthe ` SUPP propria'te buiing or lbrushing apparatus to complete the formation of a film-like waxy coatlng of uniform thickness and to impart a olish to'the fruit. The coating thus obtalned is found to possess especially desirable characteristics both as regards effective preservation of the fruit and as enabling a good polish to be obtained. Apparently the less volatile constituents of the kerosene are retained to some extent by the waxy base, but not to such an extent as to injure the fruit or to be objectionable otherwise; and these less volatile constituents 'seem to increase the toughness and adherence of the waxy coating, and also toprovidea good polish ingredient. f

Various forms of apparatus may be' employed in treating fruit in accordance with the invention. One suitable form is shown more or less diagrammatically in the accompanying drawings, in Which- Fig. 1 is a side elevation of apparatus embodying the principles of the invention and Fig. 2 is a plan view of the same, parts being broken away or removed to disclose underlying mechanism.

In the apparatus here shown, compositionapplying means are indicated generally at 10,- evaporator or drier means at 11, and polisher means at 12.

The uni-t 10 for applying the composition comprises a plurality of parallel lnclined rubbing rolls 13 cooperating in pairs to provide runways down which fruit, such as orales 14 may pass, said rolls being supplie with the coating composition 15v from supplying tank or reservoir 16, through the agency of an applying or-transfer roll 17 journaled in the walls of the tank and frictionally driven by contact with one or more of the rolls 13. These rolls 13, which may be termed wiper rolls, are in turn driven .through suitable gearing 18, said rolls all rotating in the same' direction. Except for provision of the described means for ying coating material to the rolls,4 the unit 10 may be substantially the same inconstruction as a fruit-Polisher of the well known Stebler-Parker type, with the horsehair brushes-'spinny movement oit .e fruit towardthe discharge grooved to facilitate l im ratus for carrying out the process.v of' the` driven so that its upper pass travels toward the right in the'drawing. The conveyor is enclosed in a housing 23; and in order to expedite evaporation of the solvent from the coated fruit going through the drier, means are provided for passing a current of air in contact with the fruit, such means consisting for example, of a fan 24, drawing air and vapors out of the housing through stack 25 and discharging them through duct 26 to any desired oint. A similar housing, with I or without tlie fan, may be provided for the greater speed.

unit 10 where deemed desirableto prevent escape of va ors of kerosene; but this is not essential an is not necessary to illustrate here. The bottom of the housing 23 may be provided, if desired, with openin controlled by shutters 28 which are adjgustable by an operating lever 29 to vary the effective area of said openings and thus to govern in large measure the volume of air moved transversely of the roller-belt 21 by the fan. AThe entrance and exit openings of the drier unit may be guarded by exible boots or curtains 30 and 31, respectively.

rlhe polisher unit 12 here illustrated may be of the standard Stebler-Parker type, comprising a plurality of spirally grooved orse-hair bristle brushing rolls 32 of the same general construction and arrangement asA wiper rolls 13' already described. The polisher rolls 32 should ordinarily be considerably longer than the wiper rolls, however, and lshould be driven to revolve at n practice, four to six feet is aT good length for the wi er rolls, and `eight to ten feet or more for t epolisher rolls; while 'the w1 r rolls may advantageously be rotated rat er slowly, say to 75 R. P. M., and the I' polisher rolls at 150 R. P. M. or more, these figures being understood as merely typical and m no sense restrictive. Ther pohsher rolls' may be provided with a cover or blankv et 33 similar to 19; and fruit vis delivered to said rolls `from the drieror evaporatorl unit over chute board 34. y In employing the above described appainvention, the fruit, such as oranges', which under the usual ractice will have previously been vwashed 'an dried in the usual manner,` isdischarged from a drier of the roller. belt type indicated conventionally at D and rolls tively low speed as above pointed out, and

their function is to thoroughly rub the coating composition all over the surface ot every fruit as the fruit passes down the runways. ln passing downthe runways the fruit is under the blanket 19 which rests u on the fruit and exercises a retarding or raking action that is effective to constantly change the rotation axis of the fruit and thus ensure its being rubbed on all sides by the Wiper rolls and thoroughly coated with the paraiiin-kerosene composition. The blanket itself also assists in this rubbing and` wiping treatment. By the time the` fruit has reached the lower ends of the runways, it is thoroughly covered with a thin coating of the Huid composition which still holds a very considerable part of the solvent. The fruit is now discharged from the unit 10. and rolling down over the chute board 22, pushes its way under the boot or curtain 30 and comes to rest on the roller belt 21 of the drier or evaporator unit l1. The fruit is carried slowly through this evaporator by the roller belt conveyor and Iis meanwhile exposed to a currentl of air induced by the suction fan 24, and warmedI if desired. Since-the rollers of the roller belt turn about their own longitudinal axes asv llllll the belt moves forward and fruit carried thereby is constantly turned over and over and Iin that way exposed on all sides to the full evaporating effect of the air current. Consequently the kerosene is volatilized to a considerable extent and carried away, leaving a con ealed or solid film-like coating of para n on the fruit. rIlhe roller belt conveyor discharges the fruit under boot or curtain 31, whereupon it rolls down the chute board 34 and enters the up er ends of the runwa s between the polls er rolls 32 of the polisher unit 12. These rolls most desirably rotate ata considerably higher rate of speed than the wiper rolls 13, as previously pointed out; and asthe paraiin coati on the fruit is now comparatively solid and suiciently free from solvent to prevent its being sticky or adhesive, the soft polishing surfaces of the fruit. The use' of the blanket 33, which assists in varying the axis of rotation of the fruit as it passes down the runways, is optional but desirable in favoring thorough '130 polishing of the fruit over Iits entire surface. prepared and homogenized or emulsified, are When it reaches'the lower end of the polisher rolls 32, 'the fruit is then discharged to the grading belt (not shown) and ,is thereafter graded and sized in the manner well understood in theart and unnecessary to describe here.

The relative 'proportions of waxy mate-A rial and kerosene in the coating mixture may vary within reasonably wide limits. A creamy composition prepared by mixing O' parts of commercial paraffin and 70 parts of kerosene, by volume, has given excellent results in treating California oranges; but the proportion of parafin may be eatly in'- creased, especially ifthe mixture e homogenized or emulsified by relatively high speed agit-ation in suitable emulsifier apparatus. Such treatment ensures that the composition be reasonably fluid and readily spreadable in a thin film, even though the proportion of parain be high. 'In practice, the mixture may contain as little as one volume of paraffin to three of kerosene, or as much as three-volumes of paraffin to one of kerosene. These proportions are mentioned to indicate a typical working range and are not intended as restrictive.

In preparing the coating composition, a convenient procedure is to -thoroughly liquefy the paraiiin by heating and then adding the desired amount of kerosene thereto while stirring. After the mixture has cooled, it may advantageously be homogenized with the aid of a fairly high speed emulsifier or homogenizer.

The paraffin-kerosene mixture may also advantageously contain a quantity of finely divided solid matter of harmless character that serves, amoung other things, to facilitate evaporation of the solvent to the extent i desired. Ordinary cooking starch is an ideal substance for this additional effect o improving the polish obtained on the fruit.` The dry starch may be added after the parain wax and kerosene have been mixed and before treatment in .the emulsifier. Parailin oil may also sometimes be' used to advantage in small proportions in the mixture where starch is employed. The amount of starch used may vary depending upon the consistency .and other pro erties desired. Typical mixtures are as fol ows all parts being by volume:

(1) 1 part kerosene, 1/2 part parain wax, 1 to 2 parts starch.

(2)1 part kerosene, .1,41- part parain wax, 2 parts starch.

(3) 1 part kerosene, 1,@ part parain wax, 1/4 part parain oil, 21/1 parts starch.

(4) 1 part kerosene, 1A part parain oil, 21/ arts'starch.

ll) 1A part kerosene, 1 part paraiiin wax, 1 plart starch. i

purpose, and it has the he foregoing mixtures, when properly of light creamy to buttery consistencies at ordinary summer temperature and spread easily on fruit to provide a film coating.

In the foregoing specific examples, itis permissible to include also a harmless coloring agent or dye to mask the whiteness of the starch constituent and thus to render the l paraffin oil is included in the composition',

there is less necessity for adding a coloring a ent, although it may be used in that case ao if deemed desirable.

The paraffin oil mentioned in examples (3) and (4) above is the mineral oil obtainable on the market under that name. In its place may be. used other oils lthat 'are heavier than kerosene and are of the general character of light lubricating oils.

It is to be understood that, while the typical coating compositions hereinabove specifically described include only kerosene as the liquid. vehicle, the presence of other solvents also in the mixture, such as gasoline for example, is not recluded.

It is tobe note that in mixture (4) above, no arain wax is used, and the proportion o starch used is eater than in mixture (3). A mixture ike (4) offers ractical advantages in some cases for treating certain fruits. The novel compositions v of matter herein disclosed are claimed in'a thereof a' thin coating of a mixture compris-- ing paraffin and kerosene.

3.' The process of treating fresh fruit which comprises spreading over the surface thereof a thin coating of an emulsiied mixture of paraiiin and kerosene.

4. The process of 'treating fresh frulit'v which com rises spreading over the surface thereof a t in coating of a mixture comprisin paraiin and kerosene, the paraffin con- `stituting from about-25 per cent to I5-per cent of the mixture, by volume.

-5. The process of treating fresh fruit which comprises spreading over the' surface thereof -a thin coatin o a mixture comprising waxy materi and a liquid lwhich nl Y las

ccnsistsprincipa'ly of Akerosene, eveporeting oi at least a. part of the kerosene en thoroughly rubbing the fruit.

6. The -process of treating fresh fruit which comprises rubbing on. the fruit e spreadeble mixture comprising waxy me,- i-erie, ney divided solid metter, and keroserie, to provide e preservative film coating on seid fruit.

7. The process of tree'bingffrresh rij which comprises applying to the fruit e, time coetingof a, mixture comprising paraffin, starch, and kerosene, and rubbin the 'fruit to .spread the composition in e m coating thereo'ver.

n testimony whereof I hereunto ax my signature.

@weer M. Beoeme. 

